Conventionally, there is known an airbag apparatus which inflates and expands an airbag to the side of a seat of an automobile, thereby protecting a passenger at the time of a side collision. Further, regarding this type of airbag apparatus, for example, as disclosed in Japanese Laid-Open Patent Publication No. 2006-88731, such a constitution is known that an airbag is folded and accommodated in a door part on the side of a cabin, the airbag is inflated and expanded upward from the door part, thereby protecting the head or others of a passenger. This patent document describes a constitution in which after assembly of an airbag and an inflator on inner panels of door parts, a cover panel is fitted so as to cover these members and the inner panels. Then, according to the above constitution, a hinge part is formed at the cabin internal side of the cover panel, and a lid part which moves rotationally upward on the base of the hinge part on expansion of the airbag is disposed along the upper edge of the cover panel.
However, in the above constitution, the lid part is disposed along the upper edge of the cover panel, and the edge portion of the lid part is disposed as a free end. Therefore, where a door opens and closes many times or a passenger presses a door trim, it is not easy to keep a favorable appearance of the lid part.
In this respect, such a constitution can be considered that one side of the lid part is given as a hinge part and the other side thereof is given as a tear line to rip on expansion of an airbag. However, this constitution is required to meet various requirements including characteristics of preventing the airbag from deteriorating in appearance due to provision of the tear line, securing the rigidity required for cover panels and attaining a smooth rip and rotational movement at a wide temperature range.
The above-described conventional cover body which covers an airbag used in an airbag apparatus for expanding the airbag upward from the door part is required to meet various requirements including characteristics of securing the rigidity, while keeping a favorable appearance of the airbag, and attaining a smooth rotational movement of a lid part.
The present invention has been made in view of the above situation, and an object of which is to provide an airbag cover body which keeps a favorable appearance to secure the rigidity and allows the lid part to move rotationally and smoothly on expansion of the airbag and also an airbag apparatus.